scholarly journals Study of the electrical behavior in Intermediate Band-Si junctions

2013 ◽  
Vol 1493 ◽  
pp. 85-90
Author(s):  
D. Pastor ◽  
J. Olea ◽  
A. del Prado ◽  
E. García-Hemme ◽  
R. García-Hernansanz ◽  
...  

ABSTRACTIn this study we analyze the electrical behavior of a junction formed by an ultraheavily Ti implanted Si layer processed by a Pulsed Laser Melting (PLM) and the non implanted Si substrate. This electrical behavior exhibits an electrical decoupling effect in this bilayer that we have associated to an Intermediate Band (IB) formation in the Ti supersaturated Si layer. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements show a Ti depth profile with concentrations well above the theoretical limit required to the IB formation. Sheet resistance and Hall mobility measurements in the van der Pauw configuration of these bilayers exhibit a clear dependence with the different measurement currents introduced (1µA-1mA). We find that the electrical transport properties measured present an electrical decoupling effect in the bilayer as function of the temperature. The dependence of this effect with the injected current could be explained in terms of an additional current flow in the junction from the substrate to the IB layer and in terms of the voltage dependence in the junction with the measurement current.

2016 ◽  
Vol 858 ◽  
pp. 249-252 ◽  
Author(s):  
Sylvie Contreras ◽  
Leszek Konczewicz ◽  
Pawel Kwasnicki ◽  
Roxana Arvinte ◽  
Hervé Peyre ◽  
...  

In the range 80 K-900 K, we have investigated the electrical properties of heavily aluminum in-situ doped, 4H-SiC samples. The temperature dependence of the hole concentration and Hall mobility was analyzed in the model taking into account heavy and light holes. The modelisation parameters were compared with experimental values of Secondary Ion Mass Spectroscopy (SIMS) and Capacitance-Voltage (CV) measurements.


1985 ◽  
Vol 45 ◽  
Author(s):  
J.C. Bean ◽  
A.T. Fiory ◽  
L.C. Hopkins

ABSTRACTEpitaxial Ge-Si alloy films were grown on Si(100) by molecular beam epitaxy, subsequently given a shallow P implant, and subjected to rapid thermal processing. Heat treatment causes solid-phase epitaxial regrowth of the amorphized implanted layer similar to the case of pure Ge. Phosphorus redistribution, loss, and trapping at the Ge-Si/Si interface are also observed. Anomalous electrical activation is observed for P concentrations below 1 at.%, where the-carriers are either trapped or compensated at room temperature, but not below 100K. Analyses were carried out by Rutherford backscattering and channeling, secondary ion mass spectrometry, and temperature-dependent electrical transport.


1991 ◽  
Vol 240 ◽  
Author(s):  
W. S. Hob Son

ABSTRACTThe carbon doping properties of GaAs with carbon tetrachloride as the dopant source were examined using trimethylgallium (TMGa) or triethylgallium (TEGa) as the gallium precursors and arsine or tertiarybutylarsine (TBAs) as the arsenic precursors. Secondary ion mass spectrometry (SIMS) and Hall measurements (van der Pauw method) were used to characterize the epitaxial GaAs:C layers. Very high C-doping concentrations (∼1020 cm−3) could be obtained with either TMGa and TEGa. The use of TBAs instead of AsH3 led to a significant reduction in carbon incorporation, by approximately a factor of 5–10 per mole of As precursor, over the temperature range examined (520°C - 700°C). Hydrogen at significant concentrations (0.5 – 6 × 1019 cm−3) was detected by SIMS in GaAs:C layers grown at ≤550°C utilizing all four combinations of Ga/As precursors and suggested the presence of electrically inactive C-H complexes. A post-growth anneal under helium at 550°C for 60s of these samples resulted in a 50–100% increase in hole concentration by driving out the hydrogen.


1975 ◽  
Vol 53 (11) ◽  
pp. 1071-1077 ◽  
Author(s):  
Stanley D. Rosenbaum ◽  
John C. Woolley

Homogeneous polycrystalline n type samples of the alloys Ga(AsxSb1−x) and (GaxIn1−x)Sb have been prepared from a stoichiometric melt by directional freezing methods. Room temperature measurements of electrical conductivity and Hall coefficient as a function of hydrostatic pressure up to 12 kbars have been made on samples of different composition by means of the van der Pauw technique, all specimens used in the measurements being carefully selected to avoid the presence of grain boundary effects. The experimental curves of conductivity and Hall coefficient as a function of pressure have been fitted to a two conduction band model with various band parameters taken as adjustable. The curves thus fitted give consistent values of E12, the energy separation of the two bands, as a function of x. For (GaxIn1−x)Sb, the E12 values are in good agreement with those obtained previously from measurements as a function of temperature, no previous values having been published for Ga(AsxSb1−x). Approximate values for the coupling coefficient D12 of the alloys are also obtained.


2019 ◽  
Vol 966 ◽  
pp. 243-248 ◽  
Author(s):  
Dicky Rezky Munazat ◽  
Budhy Kurniawan ◽  
Agung Imaduddin

The effect of nickel substitution on the electrical transport properties of La0.7Sr0.2Ba0.1Mn1-xNixO3 (x = 0 and 0.1) manganite have been studied. The temperature dependence of resistivity of the samples shows that nickel substitution increases the overall resistivity. Exchange probability calculation shows that the ferromagnetic (FM) coupling inside the sample decreases upon nickel substitution, which induces antiferromagnetic (AFM) coupling inside the sample. These results are suitable with the reduction in the electronic bandwidth value. Comparison of experimental data with theoretical models shows that the electrical behavior of the samples is well explained by a theory based on percolation models. Present result suggests that the electrical behavior of the sample was influenced by scattering and interaction between electron, phonon, and magnon. Nickel substitution also decrease the metal-insulator transition temperature and theoretical Curie temperature from around 328 K to 249 K and around 349 K to 275 K respectively.


Author(s):  
R. Levi-Setti ◽  
J. M. Chabala ◽  
Y. L. Wang

We have shown the feasibility of 20 nm lateral resolution in both topographic and elemental imaging using probes of this size from a liquid metal ion source (LMIS) scanning ion microprobe (SIM). This performance, which approaches the intrinsic resolution limits of secondary ion mass spectrometry (SIMS), was attained by limiting the size of the beam defining aperture (5μm) to subtend a semiangle at the source of 0.16 mr. The ensuing probe current, in our chromatic-aberration limited optical system, was 1.6 pA with Ga+ or In+ sources. Although unique applications of such low current probes have been demonstrated,) the stringent alignment requirements which they imposed made their routine use impractical. For instance, the occasional tendency of the LMIS to shift its emission pattern caused severe misalignment problems.


Author(s):  
Philippe Fragu

The identification, localization and quantification of intracellular chemical elements is an area of scientific endeavour which has not ceased to develop over the past 30 years. Secondary Ion Mass Spectrometry (SIMS) microscopy is widely used for elemental localization problems in geochemistry, metallurgy and electronics. Although the first commercial instruments were available in 1968, biological applications have been gradual as investigators have systematically examined the potential source of artefacts inherent in the method and sought to develop strategies for the analysis of soft biological material with a lateral resolution equivalent to that of the light microscope. In 1992, the prospects offered by this technique are even more encouraging as prototypes of new ion probes appear capable of achieving the ultimate goal, namely the quantitative analysis of micron and submicron regions. The purpose of this review is to underline the requirements for biomedical applications of SIMS microscopy.Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue.


Author(s):  
R. Levi-Setti ◽  
J. M. Chabala ◽  
R. Espinosa ◽  
M. M. Le Beau

We have shown previously that isotope-labelled nucleotides in human metaphase chromosomes can be detected and mapped by imaging secondary ion mass spectrometry (SIMS), using the University of Chicago high resolution scanning ion microprobe (UC SIM). These early studies, conducted with BrdU- and 14C-thymidine-labelled chromosomes via detection of the Br and 28CN- (14C14N-> labelcarrying signals, provided some evidence for the condensation of the label into banding patterns along the chromatids (SIMS bands) reminiscent of the well known Q- and G-bands obtained by conventional staining methods for optical microscopy. The potential of this technique has been greatly enhanced by the recent upgrade of the UC SIM, now coupled to a high performance magnetic sector mass spectrometer in lieu of the previous RF quadrupole mass filter. The high transmission of the new spectrometer improves the SIMS analytical sensitivity of the microprobe better than a hundredfold, overcoming most of the previous imaging limitations resulting from low count statistics.


Author(s):  
K.K. Soni ◽  
D.B. Williams ◽  
J.M. Chabala ◽  
R. Levi-Setti ◽  
D.E. Newbury

In contrast to the inability of x-ray microanalysis to detect Li, secondary ion mass spectrometry (SIMS) generates a very strong Li+ signal. The latter’s potential was recently exploited by Williams et al. in the study of binary Al-Li alloys. The present study of Al-Li-Cu was done using the high resolution scanning ion microprobe (SIM) at the University of Chicago (UC). The UC SIM employs a 40 keV, ∼70 nm diameter Ga+ probe extracted from a liquid Ga source, which is scanned over areas smaller than 160×160 μm2 using a 512×512 raster. During this experiment, the sample was held at 2 × 10-8 torr.In the Al-Li-Cu system, two phases of major importance are T1 and T2, with nominal compositions of Al2LiCu and Al6Li3Cu respectively. In commercial alloys, T1 develops a plate-like structure with a thickness <∼2 nm and is therefore inaccessible to conventional microanalytical techniques. T2 is the equilibrium phase with apparent icosahedral symmetry and its presence is undesirable in industrial alloys.


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